Marine speed indicator



Oct. 30, 1951 A. URFER MARINE SPEED INDICATOR Filed Nv. 20, 1947 3 Sheet s-Sheet 1 IN VEN TOR.

Adoi/ .Urfer' A TTORNEYS.

Oct. 30, 1951 A. URFER 2,573,515

MARINE SPEED INDICATOR Filed Nov. 20, 1947 3 Sheets-Sheet 2 IN V EN TOR.

Adolf Urfer 14 TTORNEYS.

Oct. 30, 1951 URFER 2,573,515

MARINE SPEED INDICATOR Filed Nov. 20, 1947 3 Sheets-Sheet 3 INVENTOR. Ado/f Offer ATTbR/VEYS.

Patented Oct. 30, 1951 UNITED STATES PATENT OFFICE,

Adolf Urfer, Lake Oscawana, Putnam Valley, N. Y.

Application November 20, 1947, Serial No. 787,091

The present invention relates to a speed indicator of the fluid pressure type and is adapted particularly to marine uses.

Objects and advantages of the invention will be set forth in part hereinafter and in part will be obvious herefrom, or may be learned by practice with the invention, the same being realized and attained by means of the instrumentalities and combinations pointed out in the app claim. I

The invention consists in the novel parts, constructions, arrangements, combinations and improvements herein shown and described.

The accompanyin drawings, referred to herein and constituting a part hereof, illustrate one embodiment of the invention, and together with the description, serve to explain the principles of the invention.

Of the drawings:

Fig. 1 is a side elevation, certain parts being broken away for greater clarity, of a speed indicator embodying the present invention, showing the principal elements thereof including the pressure heads, the pressure gauge, and the interconnecting tubes;

7 Fig. 2 is a front elevation of the pressure gauge shown in Fig. 1 showing the calibrated dial and indicating fingerthereof Fig. 3 is a detail crosssectional view of an exhaust or hand release valve taken alon line 3--3 of Fig. 1;

Fig. 4 is a side elevation of a sailing'ship showing the position of installation thereon of the speed indicator of the present invention;

Fig. 5 is a cross-sectional view of the pressure gauge element of the speed indicator of the invention taken alongline 55 of Fig. 2;

Fig. 6 is a cross-sectional View taken along line 6-6 of Fig. 5; 1

Fig. 7 is a side elevation, partly in central section, of the operative parts of the pressure gauge element shown in the preceding figures;

Fig. 8 is a detail view partly in elevation and partly in cross section taken along line "ii- 8 of Fig.5; and v Fig. 9 is a schematic view of certain portions of the pressure gauge element shown in the preceding figures.

The present invention has for an object the provision of a sturdy and accurate speed indicator of the fluid pressure type which is particularly adapted for marine use to indicate the speedof a ship through the water. Another obj-ectis; the. provision of a speed indicator offthe type mentioned which functions-with great accuracy .1 Claim. (Cl. 73-407) despite the roll or pitch of the ship in the water.

The invention provides a speed indicator particularly adapted for marine use which measures the differential pressure between the dynamic and static heads of the water through which the ship is travelling and indicates the same in speed units, the differential pressure being measured by means of separate pressure responsive systems of substantially equal volumes, in order toobtain accurate readings under varying conditions to be expected.

Referring now in detail to the illustrative embodiment of the invention shown by way of example in the accompanying drawings, the speed indicator comprises generally the pressure gauge element 1 0 (Fig. 1'), the pressure heads or nozzles I I, and the interconnecting static and dynamic pressure tubes I2 and 1-3 respectively. The illustrative assembly of the speed indicator with the elements mentioned on a sail boat I 4 is shown in Fig. 4, the pressure gauge element it being mounted in the cock pit [5 of the boat and the pressure nozzles Ii being mounted centrally ..of the hull and forward, interconnected by tubes i2 and 13 within the hull as shown.

As shown in Fig. 1 the pressure nozzle assembly 11 comprises a fitting i6 suitably secured to the inside surface of the hull l l-of the vessel and having an extension portion 18 extending through an aperture in the hull which serves as a mounting for the Pitot tube i9 and the static tube 20. The Pitot tube i9 is provided with an orifice 21 toward the lower end thereof and said orifice is directed toward the front of the vessel, that is, in the direction of travel thereof, in order to receive the impact or dynamic head of the water. The static tube 20 is provided with a similar orifice 2-2 directed rearwardly of the vessel in order to receive and communicate through the tube the static head of the water. r

As shown, the tubes 19 and 20 .are securely set in the extension portions iii of fitting 16 to communicate with passages 23 and 24 therethrough, which, at their other ends, communicate with the tubes 13 and 12, secured in the fitting by suitable threaded unions 25 and 26.

I he dynamic and static pressures or heads of the water through which the vessel is travelling is communicated to the pressure gauge element Ill-of the speed indicator of the invention through the tubes 13 and 12 and are received there "in respective expansive Sylphon bellows which are mechanical-1y interconnected and operate to indicate by a pointer the pressure difference cf the pressure heads. -As best sl'i'own in Figs. -5, "6and 7 tively ou fitt ngs at the back of the casing which will be hereinafter described.

The means for integrating the pressure'irn duced movements of the opposed end diaphragms I of the bellows 33 and 33 comprise a V-shaped yoke 43 secured to the free end of bellows 33 and carrying rigidly at its arm ends the'irods 4| extending generally in the direction of the axis of the bellows members and along the length thereof. At their ends adjacent the free end of bellows 34 the rods ti are rigidly connected by; a flat strip of material 42 which serves as a support centrally thereof for a bifurcated connection arm 43. A similar arm 44 is secured to the end diaphragm of bellows 34 and alink 45 is pivotally connected at either end to said rms.

-At the mid-point of the length of link 35 there is pivotally connected thereto a link 46 which transfersto an indicating pointer movements of the center point of link 45, said movement being a function of ,the pressure difference of the static and dynamic pressures as exerted on the bellows 33 and 34. As shown, an L-shaped supporting arm 56 extends normally outwardly from the plate 3|, and in the head thereof and the plate there are journalled the ends of a rotatable shaft compositely formed by spindle elements 5d adjustably secured in an intervening sleeve .55. A short shaft 52 extends through and is fast in the said sleeve 55, and is pivotally connected at one end to shaft 46 carrying at its other an adjustable counterbalancing weight 53. Adjacent an end of the shaft 5!, that on oneof the spindle elements 54, there is fixed for rotation therewith a gear sector 56 having a rearward extension comprising an integral counterbalancing weights 51. The weights 53 and 51 are provided in order to insure accurate movements of the gauge members described regardless of the position the gauge may take in use. j

Longitudinal movements of the link 43 are thus translated through shaft 5| into rotary movements of gear sector 56, and the latter is in mesh with a pinion 30 fixed on shaft 3 I'. The shaft 61, with suitable bearing means as shown, is journalled in a cross head 62 extending between and aiiixed to a pair of extensions or bosses 63 of base plate 3!, and the other end of saidshaft is journalled in and extends through said base plate. The free end of shaft 6I e xtending to the opposite side of the base plate carries a pointer 64 whereby the rotary moveunits such as knots, for instance,ras shown in Fig.

2. A coiled hair spring 56 interconnects the rotatable shaft 3! and the stationary cross head 62, as shown in detail in Fig. 9 of the drawings, and rotation of the shaft to advance the pointer 64in response to the pressure difierences in 'bejl-j V lows; 33; and 34.e pandsse ds ri .whiohgxetts 7501 2 9315! W hout qep t gfr m the principles},-

of the pressure gauge element and each comprises, as shown in detail in Fig. 3, a hollow casing having a threaded plug it in one end in which the line 10hr H is fixed. A plunger '11 extends from theother end of the bore of "casing 15 and carries a sealing shoulder at to abut a casing shoulder 19 to seal the exit except when plunger 11 is longitudinally displaced. A guide member is threadedly engaged in the bore of casing 15, serves as a guide for plunger 11 and a support for coiled spring 8i tending to bias the plunger 1''! toward closed position, and is apertured at 82 to provide free communication through the casing 15.

The T connections 13 and 14 also interconnect; the tubes 12 and I3 with the tubes 31 and 38 within the gauge'casing 3D, and the detailed structure for connection M is shown in Fig.;. of the drawings. A threaded nipple portion 85 is adapted to be screwed into an aperture in a portion 86 of the back wall of casing 33 of the A smaller aperture serves to pressure gauge. accommodate the tube 38 from within the casing; and a shoulder 8'! between the apertures servesas a seat for an annular, preferably flexible packing washer 88 tightly surrounding tube 38. A coiled spring 89 seated on a shoulder 93 within the bore of nipple 85 and against the end of packing washer 88, with an intervening contact washer 9|, maintains a resilient pressure against. packing 88 to seal the tube with respect to the casing 30.

A screw 92 is threaded into a reduced portion 93 of the bore of the T connection 74 and provided with flattened threads or otherwise formed for a sloppy fit, said screw restricting fluid communication through the connection and serving to protect the bellows and other parts of the gauge from sudden large changes in pressure communicated thereto.

In the speed indicator shown and described the individual fluid systems connected to the. Pitot and static tubes l3 and '23 respectively are formed to be of substantially equal volumes, so that variations in pressure heads on the tubes brought about by pitch and roll of the vessel in choppy or stormy water will result in substantially 'equal effects upon the bellows members of the pressure gauge, such effects being can-- celled out and prevented from reaching the indicating pointer 64. Thus, the bellows 33 and 34, their corresponding connecting tubes l2 and I3, 31 and 38, H3 and H, as well as the pressure headtubes 20 and [9 are provided in substantial duplicates so that the volumes of the systems are the same and inaccuracy and agitation of the dial indication of speed is avoided at all times. 7

The invention in its broader aspects is not limited to the, specific mechanisms shown and described but departures may be madeqthere-j from, within the scope of the accompanying;

the invention and without sacrificing its chief advantages.

What I claim is:

A speed indicator for marine vessels comprising, in combination, a pair of horizontally arranged bellows elements in substantially axial alignment having fixed ends adjacent to each other and other ends movable in respectively opposite directions each said element being responsive to pressure increases or decreases from individual sources, an indicator, and means interconnecting said other ends, and indicator for positioning the indicator in accordance with pressure difierences in said bellows elements, said means including a member secured with respect to said other end of one of said elements, extending along the length of said pair of elements and having a free end substantially aligned with said other end of the other said element, a horizontally arranged link pivotally interconnected with said free end of said member and said other end of said other element, a horizontally disposed shaft transverse to the axes of said bellows elements carrying said indicator, and means for translating displacements of the midpoint of said link into rotary motion of said shaft said last means including a pinion on said shaft, a second horizontally arranged shaft transverse to the axes of said bellows elements said second shaft having a crank arm and a gear sector thereon and a counterbalance for said sector, said gear sector meshing with said pinion, and a second link pivotally interconnecting the midpoint of said first link and said crank arm. ADOLF URFER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,265,045 Pfeiffer Dec. 2, 1941 2,362,298 Newell Nov. 7, 1944 2,450,772 Watkins Oct. 5, 1948 FOREIGN PATENTS Number Country Date 99,284 France May 31, 1873 

